Where is the mitral valve best auscultated?

• A. Left fifth intercostal space, midclavicular line
• B. Left fifth intercostal space, midaxillary line
• C. Left second intercostal space, sternal border
• D. Left fifth intercostal space, sternal border

Answer: (A)

Mitral valve sounds are best heard at the heart’s apex, which sits in the left fifth intercostal space along the midclavicular line. This location overlays the left ventricle closest to the chest wall, making S1, S2, and most mitral murmurs most audible, especially when the patient is in the left lateral decubitus position and you use the diaphragm for higher-pitched sounds.

The other sites correspond to different valve areas: the aortic valve area is the left second intercostal space at the sternal border, the tricuspid area is the left fifth intercostal space at the sternal border, and the left fifth intercostal space at the midaxillary line is not the mitral apex.